Means for protecting pressure gauges on fluctuating-pressure water lines



E. A. AVERILL. MEANS FOR PROTECTING PRESSURE GAUGES 0N FLUCTUATING PRESSURE WATER LINES.

- APPLICATION HLE D MAY 8, 1920. r Llafififlfi, Patented Ailg. L 1922.

IN VEN TOR.

A T1" ORNEYS.

EARL A. AVERTLIJ. OF MOUNT VERNON, NEW YORK, ASSIGNOJR, TO LOCOMOTIVE FEED WATER HEATER COMPANY, A CORPORATION OF DELANARE.

MEANS FOR IROTECTING PRESSURE GAUGES ON FLUCTUATING-PRESSURE WATER LINES.

Application filed May 8, 1920.

To all whom it may concern:

Be it known that I, EARL A. AVERILL, a citizen ot the United States, residing at Mount Vernon. in the county of lVestchester and State of New York, have invented certain new and useful improvements in Means for Protecting Pressure Gauges on Fluctuating-Pressure Water Lines of which the following is a specification.

This invention relates to the provision of means for protecting the mechanism of a pressure gauge connected to the discharge side of a water pump which is subject to wide fluctuations in pressure conditions. It is particularly useful in connection with gauges which are used in association with the boiler teed pump of a locomotive and in connection with this description I have illustrated my invention in such an association.

In locomotive practice as it has heretofore existed, it has been customary to install a needle valve just below the pressure gauge in the engine cab which gives the readings of the pressure conditions in the discharge line of the boiler :ii'eed pump. These pressure conditions fluctuate within wide ranges and are frequently quite violent, and the needle valve has been necessary to protect the mechanism of the gauge which would otherwise be seriously damaged by the water hammer. The adjustment 01': such a needle valve must be very close and the opening through it is so fine that it very easily clogs with a slight bit of scale or dirt. hen this occurs the valve must be opened and cleaned and then reset all of which consumes time and increases the expense of maintenance.

It is the particular object of my invention to provide adequate protection for the gauge withoutthe necessity of using a needle valve such as has heretofore been considered necessary. Specifically my invention consists in the provision of an air chamber on the pressure gauge pipe connection.

The invention and its objects will be more clearly understood upon reference to the accompanying drawing, wherein the figure is a diagrammatical side elevation of a locomotive with my improvement illustrated in Specification of Letters Patent.

Patented Aug. 1, 1922.

Serial No. 380,013.

association with the discharge side of the boiler teed pump.

The boiler feed pump 1 discharges water through the pipe 2 into a feed water heater 3 from which it enters the boiler 4 through the pipe 5 and the boiler check valve 6.

The pump is connected to the supply receptacle or tender, not shown, by means of the pipe 7, said pipe constituting the suction line of the pump. The pump is actuated by means of live steam admitted through the pipe 8 and discharged through the pipe 9.

Within the cab 10 is located the pressure gauge 11 which communicates with the discharge pipe 2 of the boiler feed pump through the connection 12. Beyond the gauge at the end of the pipe 12 is located an air chamber 13.

Immediately below the gauge at the point marked 14 it has heretofore been customary, as above pointed out, to introduce a needle valve for the purpose of protecting the mechanism of the gauge against water hammer damage due to the wide fluctuations in the pressure conditions existing in the dis charge line of the pump. By providing the air chamber 13 I have found that this needle valve can be entirely dispensed with. The air chamber very adequately prevents damage to the gauge while at the same time permitting an accurate reading of the pressure as well as an indication of the pulsations.

In installations of this kind, the pulsations ot the hand on the gauge are as much a part of the required indication as the actual position of the hand and both of these are permitted by the protect-ion scheme afforded by the air chamber. The air chamber softens the blow, but does not eliminate it entirely, but only sufiiciently to prevent damage to the instrument.

The foregoing arrangement is particularly advantageous in locomotive practice. On a locomotive, because it is essential that as small and light a piece of apparatus be used as will adequately meet the require ments, the pump is operated at speeds which are higher than would obtain in stationary pump practice. Furthermore the air chamher capacity on the line is of necessity limited. Under these conditions, the arrangeinent above disclosed proves of excepsaid chamber opening into the connection tional value. Which extends from the discharge side of I claim: thepump to said gauge whereby to prevent 10 The combination with a locomotive boiler damage to the gauge. 5 feed pump of a pressure gauge: connected In testimony whereof I have hereunto to the discharge side of the pump and an signed my name.

air chamber associated With said gauge, EARL A. AVERILL 

